JPH0235281A - Motor-driven actuator - Google Patents

Abstract

PURPOSE:To prevent the position deflection of a gear by fitting a pair of gears in turnable ways onto a fixed shaft and forming one gear to be shiftable in the axial direction and forcing the gear to an opponent gear side by a spring. CONSTITUTION:A pair of gears 17 and 22 utilized for a motor-driven actuator 1 are fitted in turnable ways onto a fixed shaft 15. One gear 17 is constituted in shiftable ways in the axial direction and forced by a spring 23 in the direction separating from the other gear 22. The gear 17 is meshed with an opponent gear 19 by the forcing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric actuator that reduces the rotation of a motor using a gear mechanism and outputs it as torque via an output shaft.

[Conventional technology] An ac differential that outputs the rotation of the drive source as torque.

As a type of actuator, an electric actuator is known, which reduces the rotation of a motor using a gear mechanism and transmits the rotation to a driven side via an output shaft. This type of electric actuator typically
A manual disconnecting/disconnecting device for connecting/disconnecting the gears in the reduction gear mechanism is installed to disconnect/disconnect the rotational driving force from the motor.

This type of conventional one-motion disconnection device has a spring member such as a temporary spring interposed between a gear rotatably and slidably fitted on a fixed shaft in a gear mechanism and a housing substrate. Each time a gear on a fixed shaft is slid with an operating member, it is disengaged from the mating gear.

[Problems to be Solved by the Invention] However, in an electric actuator equipped with such a conventional L-motion connecting/disconnecting device, 1! due to the holding force of the motor and friction of the gear train. However, when the actuator is stopped at a certain position, the force to maintain that position is weak even when a load is applied, and the stop F position shifts when a load is applied. There was a problem in that the function as an actuator was degraded. In addition, backlash and axial play between the gears generate considerable noise, resulting in a problem that the environment is degraded.

[Means for solving problems]

In order to solve these problems, the present invention provides a system in which a pair of gears that constitute a reduction gear mechanism, each of which meshes with a different mating gear, is rotatably fitted onto a fixed shaft. One of the gears is formed so as to be movable in the axial direction, and a spring member is interposed between both of these gears to spring in a direction to separate them, and the movable side resists the elastic force of the spring member. An operating member is provided for moving the gear and disengaging it from the mating gear.

[For production]

The rotation of the motor shaft is decelerated by a gear mechanism and transmitted to the driven side via the output shaft. While stopped, a frictional force is generated by the spring member on the plane 1 of the pair of gears, and sufficient holding force is obtained. When the operating member is manually operated and the gear is slid on the fixed shaft 1- against the spring force of the spring member, this gear and the other gear are disengaged and the holding force by the motor is released. . When the user releases the operating member, the gear and the operating member return to the gear meshing state due to the spring member between the gears.

〔Example〕

This embodiment shows an example in which the present invention is applied to open and close a valve. Fig. 1 is a plan view thereof, Fig. 2 is a joint sectional view, and Fig. 3 is an expanded N sectional view of a reduction gear mechanism. . In the figure, the actuator 1 is equipped with a fixed hese 3 connected to a driven-side valve body (not shown) by a yoke 2, and this fixed hese 3 is formed into a rectangular box shape that opens downward. The covered cover 4 is screwed down. An output shaft 5 is rotatably supported on the cover 4 and the fixed heath 3 via bearings 6 and 7, and the output shaft 5 is inserted into the valve body (not shown) via a coupling 8. connected to the valve.

f] is an f part play 1~ formed into a rectangular plate shape, which is close to the fixed head 3 and is rotatably supported on the output shaft 5 with vertical movement regulated. An elongated hole 9a formed at the negative end of the plate 9 is fitted with a bottle 10, which is screwed into a screw hole of the fixing head 3, so as to be slidable in the length direction of the elongated hole 9a. Reference numeral 11 denotes a part play 1- which is formed in a rectangular plate shape and is integrated with the dot parts plays 1 to 9 by a stay (not shown), and has a rotating part 1''-1 on the output shaft 5. This 4] section plate 1
1, a motor 12 is fixed with a motor shaft 13 facing downward. A small gear 14 is fixed to the motor shaft 13, and a gear shaft 15 is fixed at both ends to the lower play 1-11.9. A small gear 17 is integrally formed with gear 1G.
1], 9 is fixedly supported, and on this gear shaft 18, a gear 19 that meshes with the small gear I7 and a small gear 20 below the gear 19 are integrally formed and rotatably fitted. A small gear 20 is mounted on the gear shaft 15.
A gear 22 integrally formed with the gear 1 and rotatably fitted thereto.
It meshes with the. A compression spring 2;3 is interposed between the gear I6 and the gear 22, and the compression spring 2;3 is interposed between the gear I6 and the gear 22.
A manual disconnection/disconnection mechanism (described later) is provided for disconnecting/disconnecting the engagement between the gear 7 and the gear 19.

On the other hand, on the F part plate lll-, there is a bottom plate 24.
is fixed, and a gear 26 is attached to the shaft thereof. Reference numeral 28 denotes an output shaft gear which is rotatably attached to the output shaft 5'', and a segment gear 29 for torque transmission in a ja-shaped shape that meshes with the small gear 21 and a gear 26 of the potentiometer 24 that meshes with the output shaft gear 28 is an output shaft gear. It is integrally formed with a circular segment gear 30 for transmitting rotation angle in a stepped manner, and is configured to transmit the rotation of the small gear 21 to the output shaft 5 and the rotation of the output shaft 5 to the potentiometer 24. has been done.

Gear] Above the fi, there is a cylindrical bearing portion 31 with a bottom.
is integrally formed with the cover 4, and a manual disconnection pin 32 serving as a manual disconnection member with its tip facing the top surface of the gear 16 is supported on the bearing portion 31 so as to be movable in the upper direction. There is. By doing this, when the manual disconnection pin 32 is pushed down against the elastic force of the compression coil spring 23 provided between the gears 16 and 22, the gear I [i, I7 is pressed down against the compression coil spring 23. The small gear 17 and the gear 19 are disengaged from each other by descending while being compressed.

A stud S'84 having a rectangular cross section is protruded from one end of the lower play 1-9.
On both sides of the pin 35, long wooden pins 35 and 3 project from the fixed base 3, and are fixed to the Y cover 4 at one end of the pin 35. In addition, L division play l
-11 is provided with a notch 37 into which the pin 35 is inserted. A spring shaft 38 is fitted into the shaft hole of the stan F 34 through a flanged bushing so that it can move forward and backward in the axial direction. A threaded hole in the plate 39 is screwed into the plate 39 so that it can be adjusted forward and backward.Another plate 40 is connected to the bracket 38-1 between the plate 31 and the stand 1-3.
4 and pin 3! 'i, 36 are fitted in between, and this play 1-3! 3 and the head of the spring shaft 38, a compression coil spring 41 has both ends connected to the spring receiver 4.
2.43 and is interposed with a slight accumulation of elasticity. And Shibe plate l I l: lkoha,
A pair of limit switches 4/l and /15 which stop the motor 12 by opening their contacts are fixed, and the pins 35 are opposed to their contacts.

Due to this configuration, when the valve is fully opened and fully closed, and when the valve side is overloaded, the play 1- of the -1-knee F is
1m! ] and the entire gear reduction mechanism horizontally rotates in the forward or reverse direction around the output shaft 5, and the contact point of one of the glue I switches/14.45 is opened by the pin 35, and the motor 12 is stopped. . In this case, stud 34
No matter which direction the spring shaft 38 moves, each time the plate 39 or plate 40 is restricted from moving by the pins 3fi and 37, the compression spring 41 is compressed and elastic force is accumulated. It is composed of

The operation of the electric actuator configured as shown below will be explained. When the motor 12 is started, the rotation of the motor shaft 13 is decelerated by the gear l/1.16.17.19.20 and transmitted to the gear 22,
It is transmitted to the output shaft 5 by the meshing of the segment gear 29 and the potentiometer 24 by the meshing of the segment gear 30 and the gear 26. When the valve opens by a predetermined opening and the output shaft 5 rotates by a predetermined angle, the potentiometer 24 detects this due to the engagement of the gears 30 and 26 and issues a signal, the motor 12 stops and the valve opens to the predetermined opening. Stop at.

If a foreign object gets stuck in the valve during the opening operation of the valve, causing an overload, the reduction gear train stops and only the motor shaft 13 attempts to continue rotating, causing the upper and lower plays 1 to 11.9. The gear train rotates around the output shaft 5 together with the gear train. As a result, the contact of the limit switch 44 or 45 is opened by the pin 35, so the motor 12 is stopped and the coils of the motor 12 are prevented from being burnt out due to overload.

Even if a load is applied while the gears 16 and 22 are stopped, the compression coil spring 23 is interposed between the gears 16 and 22, and its elasticity generates a frictional force on the plane of the gears 16 and 22, so there is sufficient holding force. is obtained, and a) 7 misalignment does not occur.

When the manual disconnection pin 32 is pressed down against the elastic force of the spring 23, the gear I6. I7 is compressed IIl file 2
Since the gear 1719 is disengaged while being compressed, the transmission of rotation is cut off. In this case as well, sufficient holding force can be obtained. When the hand is released from the manual disconnection pin 32, the gears 17 and 19 return to the meshing state due to the elastic force of the gear 16, the manual disconnection pin 32, and the compression coil spring 23.

FIG. 4 is a developed vertical sectional view of a reduction gear mechanism showing another embodiment of the present invention corresponding to FIG. It has been intervened. The other configurations are the same as those of the previous embodiment. By doing this, a frictional force is generated by the leaf spring 46 on the plane of the gear 16, 22, and a sufficient holding force is obtained, as in the previous embodiment.

In each of the above-mentioned embodiments, an example was shown in which the present invention was implemented for opening/closing a valve, but it can be implemented in various other types of equipment, and the same effects can be obtained.

〔Effect of the invention〕

As is clear from the explanation below, in the electric actuator according to the present invention, a pair of gears constituting a reduction gear mechanism and meshing with respective mating gears are rotatably fitted on a fixed shaft. One of the gears is formed to be freely movable in the axial direction, and a spring member is interposed between both of these gears that springs in a direction to separate them, and the spring member moves against the springing force of the spring member. +iI By providing an operating member that moves the gear on the movable side and disengages it from the mating gear, a single spring member can generate a frictional force on two opposing planes, and a sufficient holding force can be obtained. Therefore, even if a load is applied while the actuator is stopped, positional deviation does not occur, and its function as an actuator is improved. In addition, the gear's hacklash and axial play are reduced due to the frictional force of the gear.
In addition to reducing static noise and improving the environment, the manual disconnection member can be returned to its original position using a spring member that generates frictional force.
In addition, by providing a pair of gears on one shaft 1-, the structure becomes compact with only 1 g of cage, and 2! The strike is completely destroyed.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the electric actuator according to the present invention, FIG. 1 is a top view thereof, FIG. 2 is a vertical cross-sectional view, and FIG. 33 is a developed longitudinal cross-section of a reduction gear mechanism. side view,
FIG. 4 is a developed longitudinal sectional view of a reduction gear mechanism corresponding to FIG. 3, showing another embodiment of the present invention. ■... Actuator, 5... Output shaft, 12...
・・Motor, 1/l, 17. 2+) 2]・・
Small gear, 15...Gear shaft, IFi, ]922...
・Gear, 23...Compression coil spring, 32...Manual disconnection pin 1.46...Temporary spring. Patent applicant Yamatake Honeywell Co., Ltd. Agent
Masaki Yamakawa (2 people)” - Toreiho (self-authored) 9.2, 63, Showa.

Claims (1)

[Claims] In an electric actuator in which the rotation of a motor is decelerated by a gear mechanism and transmitted to the driven side via an output shaft, a pair of gears that constitute the gear mechanism and each mesh with a different mating gear are mounted on a fixed shaft. The gears are fitted rotatably and one of them is formed to be movable in the axial direction, and a spring member that springs in the direction of separating them is interposed between the two gears, and the spring member is elastic. An electric actuator comprising an operating member that moves the movable gear against a force to disengage it from a mating gear.